The Batcache is actually real software developed in-house by Automattic to help power its blog hosting service.

The X-hacker header, pretty much a smart wanted ad. It turns out that this recruitment trick isn’t unusual. Automattic is casting a pretty wide net since all sites on the WordPress.com platform include it. You’ve probably come upon it in the past.

Speaking of that, GigaOm.com (which uses WordPress.com) has a pretty fun addition to the standard WordPress.com response headers, a kind of recruitment override…

Phew…

Going through HTTP headers to find something odd and interesting is a bit like sifting for gold. You have to go through a lot of dirt, but you can end up with some nice little nuggets along the way. We hope you liked these!

A final little side note: If you like this stuff there’s also a pretty awesome post over at netthing.org about unconventional HTTP headers that you might want to check out.